Obtaining Server Logs

If you get an error from the client, such as:

ERROR 2013 (HY000): Lost connection to MySQL server during query
No connection. Trying to reconnect...

You can get the server logs from the system.tracing table(level=50 only shows the ERROR logs):

note

Databend uses tokio-tracing to trace logs, where the default timezone is UTC and cannot be changed through the Databend timezone setting, therefore the time in the traced log will always be in UTC, and not reflect your local time.

SELECT * FROM system.tracing WHERE level=50;
+------+----------------+----------------------------------------------------------------------------------------------------------------------------------+-------+----------+--------+-------------------------------------+
| v    | name           | msg                                                                                                                              | level | hostname | pid    | time                                |
+------+----------------+----------------------------------------------------------------------------------------------------------------------------------+-------+----------+--------+-------------------------------------+
|    0 | databend-query | [EXECUTE - EVENT] panicked at 'index out of bounds: the len is 1 but the index is 1', common/datablocks/src/data_block.rs:104:17 |    50 | thinkpad | 646495 | 2021-11-17T03:31:27.656710495+00:00 |
|    0 | databend-query | [EXECUTE - EVENT] panicked at 'index out of bounds: the len is 1 but the index is 1', common/datablocks/src/data_block.rs:104:17 |    50 | thinkpad | 646495 | 2021-11-17T03:31:27.703538995+00:00 |
|    0 | databend-query | [EXECUTE - EVENT] panicked at 'index out of bounds: the len is 1 but the index is 1', common/datablocks/src/data_block.rs:104:17 |    50 | thinkpad | 646495 | 2021-11-17T03:31:27.755246715+00:00 |
|    0 | databend-query | [EXECUTE - EVENT] panicked at 'index out of bounds: the len is 1 but the index is 1', common/datablocks/src/data_block.rs:104:17 |    50 | thinkpad | 646495 | 2021-11-17T03:31:51.861038285+00:00 |
|    0 | databend-query | [EXECUTE - EVENT] panicked at 'index out of bounds: the len is 1 but the index is 1', common/datablocks/src/data_block.rs:104:17 |    50 | thinkpad | 646495 | 2021-11-17T03:31:51.912497882+00:00 |
|    0 | databend-query | [EXECUTE - EVENT] panicked at 'index out of bounds: the len is 1 but the index is 1', common/datablocks/src/data_block.rs:104:17 |    50 | thinkpad | 646495 | 2021-11-17T03:31:51.956650623+00:00 |
+------+----------------+----------------------------------------------------------------------------------------------------------------------------------+-------+----------+--------+-------------------------------------+